October 6 Update: Reliable Firing Achieved
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Steven Sesselmann.
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October 7, 2010 at 11:01 pm #972
TulseParticipantI’m sure this will be up on the main site shortly:
On September 29, we finally achieved repeatable firing of all attached capacitors. That day, and on September 30 and October 1, we fired all eight attached capacitors in 11 successive shots with only three pre-fires.
[…]
In both of the shots with yields over 10^11 neutrons, we observed average ion energies over 100 keV for the first time with FF-1, getting us into the range useful for pB11 fusion. In shot 93002, we measured an average ion energy of 143 keV, and in shot 100102, we measured 108 keV (equivalent to 1.6 billion degrees K and 1.2 billion degrees K respectively). The important thing is that we are confining ions of this energy for tens of ns. If we can achieve the same conditions with pB11 as we did with D in shot 93002, we would expect a pB11 fusion yield of about 0.5 J.
October 8, 2010 at 1:16 am #8524zapkittyParticipantHah! More stonewalling! It’s always the same with you fusion types… “Fusion is always 30 days away.”
😉
October 8, 2010 at 3:06 am #8525KeithPickeringParticipantI hate to be a wet blanket … but half a joule per pinch, even at a 100 hz firing rate, is just 50 Watts …
I guess it’s the demonstration of any net energy, no matter how small, that counts.
October 8, 2010 at 3:32 am #8526zapkittyParticipantKeithPickering wrote: I hate to be a wet blanket … but half a joule per pinch, even at a 100 hz firing rate, is just 50 Watts …
I guess it’s the demonstration of any net energy, no matter how small, that counts.
Wouldn’t “net” energy be any yield that exceeded the cap’s input energy?
I’d assume, perhaps mistakenly, that at this point they’re just getting started on the “we have fusion” part… with actual net power yields coming later.
edit: “started” for “stared”
October 8, 2010 at 4:20 pm #8529AeronautParticipantzapkitty wrote:
I hate to be a wet blanket … but half a joule per pinch, even at a 100 hz firing rate, is just 50 Watts …
I guess it’s the demonstration of any net energy, no matter how small, that counts.
Wouldn’t “net” energy be any yield that exceeded the cap’s input energy?
I’d assume, perhaps mistakenly, that at this point they’re just getting started on the “we have fusion” part… with actual net power yields coming later.
edit: “started” for “stared”
To split hairs, repeatably producing more energy than the cap bank supplied (not contained at the beginning) just might count for the historic first of over-unity operation, provided it is presented in the context of a one-shot fusion research reactor. Still very flimsy to build a headline ariund. I’d use that well-documented accomplishment as at least one ace in the hole.October 8, 2010 at 5:56 pm #8530MTd2ParticipantLet’s see, going from 1MA to 3MA you’ve an expected yield of 200X bigger. Adjusting the pinch, 8 times more, achieving 600KV of ion themperature, 5 times more. So, up to 8000 more, at least 4000KJ of output per shot. 🙂 So, the biggest gain is by increasing the current!
October 8, 2010 at 6:25 pm #8531TulseParticipantAeronaut wrote: repeatably producing more energy than the cap bank supplied (not contained at the beginning) just might count for the historic first of over-unity operation
Exactly — repeatably demonstrating over-unity fusion energy would be truly earth-shattering news, an achievement well beyond what decades and hundreds of billions of dollars of conventional fusion research has produced. I would certainly hope that LPP wouldn’t use a monthly new update to announce such a thing.
Those closer to the project may correct me if I’m wrong, but it seems like we’re still very much in the “shakedown” phase of the research project, basically getting to the point where the equipment functions reliably. It’s only after the gear is solid and stable that things can progress to the more interesting work (and presumably, with reliable equipment, that progress can be very rapid as one tweaks variables).
October 9, 2010 at 7:50 am #8538Ivy MattParticipant100+ keV ion energies: good news indeed. Now looking forward to 1+ joule of fusion energy firing on all twelve cylinders. I’m not sure how you get from 1 to 10,000+ joules in a few months, but I guess I’ll just sit back and watch what happens next.
One thing I like about this report is that it touched on pretty much everything: kV, MA, torrs, keV, and joules. (Am I missing anything?) If each update does that, then it’s fairly simple to follow progress from one update to another. Once you’ve got your 1+ joule, it would be nice to see an update to the fusion yield [del]timeline[/del] chart, if only to show skeptics that it’s not so much a logarithm approaching an asymptote as it is a hyperbolic sine. 😉
October 9, 2010 at 7:11 pm #8545MTd2ParticipantIvy Matt wrote: I’m not sure how you get from 1 to 10,000+ joules in a few months, but I guess I’ll just sit back and watch what happens next.
That’s because most of it relies on simply increasing some of the input parameters slightly. Meaning, 3 times the current means 200 more energy. Changing from boron to h means 3x more energy, varying up and down the pressure of the gas vs. pinch time means another 10x, and so on.
October 11, 2010 at 8:31 am #8555AugustineParticipantKeithPickering wrote: I hate to be a wet blanket … but half a joule per pinch, even at a 100 hz firing rate, is just 50 Watts …
I guess it’s the demonstration of any net energy, no matter how small, that counts.
Yes, it is the demonstration of net energy. Think of it this way, how many years until ITER shows a demonstration of net energy? Decades?
Just as important as the demonstration of net energy is the verification of the scaling laws. Scaling to the fifth power of the current would mean that you would have a reasonable reactor at 100Hz with 2MA.
And wonderful photos to boot!
October 11, 2010 at 8:34 am #8556AugustineParticipantTulse wrote:
repeatably producing more energy than the cap bank supplied (not contained at the beginning) just might count for the historic first of over-unity operation
Exactly — repeatably demonstrating over-unity fusion energy would be truly earth-shattering news, an achievement well beyond what decades and hundreds of billions of dollars of conventional fusion research has produced. I would certainly hope that LPP wouldn’t use a monthly new update to announce such a thing.
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If LPP achieves this then you need to do two things:1. Upgrade the web site. You will be the most popular web site on the planet for a few days.
2. Make a better video explaining how this works (step by step, perhaps even baby step by baby step)
3. Constantly reinforce the point that there is no nuclear waste, only helium- the stuff in children’s balloons!
October 12, 2010 at 4:20 am #8566TulseParticipantAugustine wrote: Think of it this way, how many years until ITER shows a demonstration of net energy? Decades?
Like all Big Fusion projects, twenty years. It’s always twenty years.
October 15, 2010 at 6:48 am #8599Steven SesselmannParticipantHow do they measure ion energies?
Steven
October 15, 2010 at 2:31 pm #8605jamesrParticipantSteven Sesselmann wrote: How do they measure ion energies?
Steven
From the spread in neutron flight times.
A D-D fusion reaction always releases neutrons with fixed energy (ie. velocity). But this velocity is in the centre of mass frame of the two fusing deuterium ions. So the actual velocity of the neutrons will be spread by the thermal velocity of the ions, ie. whether they were going towards or away from the detector at the time.
Since you know the distance the detector is away you can find the velocity from the flight time. The shape of the velocity curve should be roughly Maxwellian, so by fitting a curve to it you get the equivalent temperature.
October 15, 2010 at 11:06 pm #8611Steven SesselmannParticipantThat sounds like an almost impossible task…, I assume this method can only work with pulsed fusion. If the fusion was a steady state reaction it would not be that simple, unless you could measure the neutron energy in a scintillator.
Steven
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